The dimensions of roofs are measured on a frequent basis by insurance adjustors, roofers and other professionals. At present, roofs are typically measured using two types of measuring tapes. One type of measuring tape is a semi-rigid automatic-retrieval tape available in 25- and 30-foot lengths, such as those produced by Stanley and Lufkin. A second type of measuring tape is a flexible 50- or 100-foot tape which is retrieved by use of a manual crank system. Each type of measuring tape has problems when used on steep, dangerous or unclimbable roofs. These problems will be addressed separately below.